Hello, my name is***** and I have over 20 years of experience as a veterinarian. I am sorry to hear about your girl's gagging episodes, and sticking out her tongue. I fully understand your concern.
This can be a sign of nausea but it can also be a sign of oral pain due to an infected tooth or a foreign body caught under her tongue, on the roof of her mouth, or in the back of her throat. Sometimes it is a sign of an oral tumor. If she is an older girl nausea due to organ failure is possible.
It can also be due to a nerve problem that is making it difficult for her to control her tongue or close her mouth properly.
Is she is eating and drinking fairly normally for her? If so a nerve problem or organ failure seems less likely, but it is important to watch and see if she is continuing to eat and drink without any trouble holding onto her food.
This behavior can also be a response to eating a bitter bug or plant piece.
Since this is a recent thing for her if she is drooling, if she has any sort of eye or nasal discharge, and her gums look irritated or there are ulcers present in her mouth this may be related to an upper respiratory infection called Calici virus.
Of course the other possibility is feline asthma. We can usually diagnose them with radiographs when they are showing symptoms. But if we don't catch them during an episode radiographs can look clear.
Heart disease is a possibility. If her gums and tongue aren't a nice bubblegum pink, but instead appear blue or gray in color ideally your veterinarian would take radiographs which would allow them to visualize heart enlargement or pulmonary edema (fluid in the lungs) if he had a cough related to heart disease.
The other possibility unfortunately is that she has a mass or masses in her lungs irritating his bronchioles and causing her to cough.
If she has no other signs of a respiratory infection (eye or nasal discharge) it would be very reasonable to check for a foreign body or ulcer or mass in her mouth, or a bad tooth (teeth), and check a heartworm test.
If those aren't diagnostic and she isn't improving the next step would be to take chest radiographs and compare them to the previous ones taken if she has ever had any taken to see if there have been any changes.
If her radiographs look suspicious for asthma or even if they look clear when she isn't coughing and there is no sign of edema or a mass in his lungs then trying a course of bronchodilators (oral like theophylline or inhaled) and inhaled cortisone (like fluticasone) would be reasonable. In most cases inhaled formulation of both drugs work best. In some cases your veterinarian may start with an injection of steroids to get her some immediate relief. If you use inhaled formulations of steroids they can work directly on the lungs, and thus tend to work better, and because they aren't systemic they have less side effects.
Rarely a nasopharyngeal polyp or a fungal infection can be the cause of a cough/gag, so looking further with sedation and a nasal scope, as well as a look behind the soft palate may be needed, if she isn't coming along.
I would expect her to have a nasal discharge with a fungal infection but in some cases early on the discharge only drains down the back of the throat.
If it comes along with facial swelling or hives it could be related to an allergic reaction.
I would look in her mouth, or if you can't look your veterinarian can take a very close look under sedation to find the problem. But if she will let you examine the inside her mouth closely for swelling, reddened areas or any sign or trauma or a foreign body, especially under her tongue.
If her color is good and there aren't any obvious signs of anything wrong in her mouth you can give her an acid reducer to try and settle her stomach in case this is related to nausea.
1) Pepcid-ac (famotidine) at a dose of one quarter of a 10mg tablet per 5 to 10 pounds of body weight every 12 hours.
2) Prilosec (omeprazole) at a dose of one quarter of a 10mg tablet per 5 to 10 pounds of body weight every 24 hours.
These will reduce stomach acid and should help settle her stomach. These are quite safe and can be used for several days if necessary.
Then start a bland diet of 2/3 boiled, white, skinless chicken and 1/3 plain, boiled, white rice. Give small meals several times a day. Feed the bland diet for several days, then if she seems better start mixing in her regular diet and slowly convert her back over a period of 5 to 7 days.
If she is repeatedly attempting to vomit, she has facial swelling, or she is pawing at her mouth or unable to drink water normally then I recommend she see a veterinarian immediately as this can also be a sign of an allergic reaction or something stuck in her mouth.
If her symptoms continue in spite of using an acid reducer and a bland diet then she should see her veterinarian for an examination, some blood tests to look for underlying metabolic disease, and probably sedation to look closely in her mouth and take dental radiographs.
Please let me know if you have any further questions.
Best of luck with Boots, please let me know if you have any further questions.